The present rotary pull down drive is used in connection with water well drilling or blast hole drilling to remove overburden in open pit coal mining and related drilling areas. In such drilling the tubular drill pipe mounting drill bits of the desired construction is projected through an upright tubular output shaft which is supported and journaled for rotation upon a vertical axis upon a suitable platform. Various mechanisms have been employed for establishing a driving relationship between the output shaft and the drill pipe. Various mechanisms have heretofore been employed for causing the drill pipe to advance into the ground or to be withdrawn therefrom.
There has long existed the need for an improved rotary pull down pull up drive for such drill pipe which in a simplified manner will effect rotation of the drill pipe and at the same time is adapted to feed the drill pipe downwardly and alternately upwardly in simultaneous actions.